The primary function of the hip joint is to support the weight of the body in both static (e. g. standing) and dynamic (e. g. walking or running) postures. The hip joints are the most important part of the body in retaining balance. The pelvic inclination angle, which is the single most important element of human body posture, is adjusted at the hips. It is no wonder then, that injury of the hip joint can be painful and debilitating.
The hip joint, scientifically referred to as the acetabulo-femoral joint, is the joint between the femur and acetabulum of the pelvis. The femur head is globular and forms rather more than a hemisphere, is directed upward, medial-ward, and a little forward, the greater part of its convexity being above and in front. The head of the femur meets with the pelvis at the acetabulum, forming the hip joint.
Three bones come together to form the acetabulum; the ischium; the ilium; and the pubis. The acetabulum is also home to the acetabular notch, an attachment site for ligaments that hold the head of the femur securely in the acetabulum. The well-fitting surfaces of the femoral head and acetabulum, which face each other, are lined with a layer of cartilage and lubricated by a thin film of fluid. Friction inside a normal hip is less than one-tenth that of ice gliding on ice, however, friction increases as the cartilage and ligaments are damaged due to injury.
The hip muscles act on three mutually perpendicular main axes, all of which pass through the center of the femoral head, resulting in three degrees of freedom and three pair of principal directions: Flexion and extension around a transverse axis (left-right); lateral rotation and medial rotation around a longitudinal axis (along the thigh); and abduction and adduction around a sagittal axis (forward-backward); and a combination of these movements (i. e. circumduction, a compound movement in which the leg describes the surface of an irregular cone).
Athletes can experience hip pain as a result of many conditions: bone fractures; muscle strains and tendinitis (iliopsoas and proximal hip quadriceps strains; iliotibial (IT) band syndrome; muscle tendon bursitis; contusion (bruise, commonly called a hip “pointer”); labral tears of cartilage; osteoarthritis; and emoroacetabular impingement (FAI, a condition where the bones of the hip are abnormally shaped, and rub against each other and cause damage to the joint).
Hip fractures commonly involve a bone break just below the femur head. Such fractures are rare in young people and tend to be caused by falls, car accidents and sports injuries. Symptoms include pain, stiffness, and loss of strength and range of motion. Muscle strains and tendinitis arise when muscles and tendons of the hip and groin region are subject to overuse injuries. Symptoms include aches, stiffness, and pain in the front or back of the hip when one tries to flex the hip while running or kicking. IT band syndrome results when the belt of fibrous tissue that runs along the outside of the hip to the knee becomes too tight and rigid. When the knee is flexed, the IT band grates against the edge of the hip bone, causing irritation. The pain is usually felt outside the hip and along the knee, especially with walking and running. Bursitis arises when the bursa sacs and other soft tissue around the hip become inflamed and painful, especially with walking and running. Pain is often experienced when lying on the affected side of the body. Hip “pointer” injuries often occur during football or hockey, when an impact to the rim of the pelvis results in internal bleeding. Pain and soreness are experienced on the side of the hip and may make walking or skating difficult. The injury can be visible—swollen and bruised. Labial tears cause pain in the hip and may be accompanied by a clicking sound (with movement). When these tears occur in athletes, their ability to run and jump is significantly limited. Osteoarthritis, essentially hip pain that persists, may signal arthritis, especially in older athletes. Limping while walking is also a common hip complaint and may be related to stiffness and pain in the hip joint. Eventually, there may be nothing left to prevent direct bone-on-bone friction within the joint, which causes pain with movement and weight-bearing activities.
Sports-related hip pain is usually the result of a traumatic event, such as when someone falls or sustains a hard impact. Such pain also may stem from extensive, repetitive motion. Hip injuries may also happen with a single event of too much strain or stress to the joint. Most sports-related hip problems will typically respond to conservative treatment. Surgery rarely is needed for general hip injuries. Labral tears may require arthroscopy and hip or femur fractures likely need surgical repair. Most hip fractures will require surgery to stabilize the joint. The extent of surgery depends on the exact fracture. Muscle strains, tendonitis, bursitis, and iliotibial band syndrome can be managed through non-surgical methods. Hip “pointer” treatment will usually require activity modification and padding until the bruise, or hematoma, resolves. Labral tear is treated by arthroscopic surgery. Osteoarthritis treatment will depend on the extent of arthritis in the joint and its impact on function. Non-operative treatments include: modifying activity, icing, medication, and/or rehabilitation.
Another non-operative treatment for hip injury and hip-injury related pain is use of a hip brace. Hip braces are commonly employed both to prevent hip-joint injury and alleviate pain. Hip braces of the prior art are designed to support the hip and hip-joint by aligning the hip in a certain orientation or by restricting joint or hip motion. This is often accomplished through the use of multiple straps, or rigid or semi-rigid, materials that help align the hip in a certain orientation, thereby immobilizing the hip joint.